This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The purpose of this research study is to understand the effects of oral aspirin taken daily with an arginine-restricted diet on certain colorectal cancer biomarkers in treated colon cancer patients. Patients with colon cancer are at high risk for recurrence and for development of secondary colorectal cancers in the future. Specific chemicals (polyamines, prostaglandins) in the body referred to as biomarkers can be measured to help understand a person s risk for developing colorectal cancer. Specific biomarkers associated with colorectal cancer have been identified in prior laboratory studies. By measuring these predefined biomarkers before and after the study intervention, we can assess how they are affected by the intervention, and gain knowledge about their usefulness in colon cancer patients on clinical trial. This study is a Phase IIa clinical biomarker study, using oral aspirin 325 mg taken daily with an arginine-restricted diet designed to reduce arginine intake by at least 30% during the 12-week study period. The biomarkers will be obtained from patient by performing endoscopy (a procedure used to look at the inside of the bowel, rectum and colon) and biopsy (taking samples of tissue), phlebotomy (drawing blood), and urine collection. Biopsies are done to evaluate changes in tissue content that may relate to early events in colon cancer formation. This was the procedure used to diagnose your condition initially. There will be 24 patients enrolled into this study performed through University of California Irvine Medical Center.